The BEST episodes directed by Jeff 'Swampy' Marsh

#1 - Toy to the World

Phineas and Ferb - Season 1 - Episode 16

Based on the fact that a platypus doesn't do very much, Phineas and Ferb create a wooden toy version of Perry to sell to a toy company. Meanwhile, the real Perry heads off to stop Doofenshmirtz from building the Great Wall of the Tri-State Area and starting up toll booths at the only exits.